Cement
Clinker cooler
Also known as grate cooler, cement cooler.
A clinker cooler (most commonly a grate cooler) quenches hot clinker discharged from the rotary kiln at ~1,400 °C down to ~100 °C using forced ambient air blown upward through a perforated grate. Hot air recovered from the cooler is used as secondary combustion air at the main kiln burner and as tertiary air at the calciner via the tertiary air duct (TAD).
Cooler-related fouling
The cooler itself rarely fouls but generates substantial fines that drop out into hoppers below and along the TAD:
- Cooler dust hopper bridging — hopper outlets clog with fine clinker dust
- Pulse-jet filter pluggage on cooler vent baghouses
- TAD bottom dropout along the air route to the calciner
Sonic-horn duty
Sonic horns installed on the cooler dust hoppers prevent bridging and maintain dust extraction. The horns must tolerate the high-temperature environment immediately below the kiln-discharge zone; stainless-steel construction is standard.
Related terms
Related terms
- ClinkerClinker is the dark, hard nodular intermediate product of cement manufacture, formed by burning raw meal at 1,450 °C in the rotary kiln before grinding to cement powder.
- Rotary kilnA rotary kiln is a long inclined rotating cylinder where preheated raw meal is burned at 1,450 °C to form clinker. The heart of every cement plant.
- Tertiary air ductThe tertiary air duct routes hot air from the clinker cooler to the calciner combustion zone, bypassing the kiln. Dust dropout in the TAD is a recurring operational issue.
- Sonic hornA sonic horn is a pneumatically-driven low-frequency sound emitter (typically 60–400 Hz at 140–180 dB SPL) used to dislodge particulate fouling from boilers, ESPs, baghouses and process vessels.